Hi,This may be a really simple question, can someone tell me why verbs with stressed syllables, but also have a consonant and vowel, do not double up. For example, stop becomes stopping, but shout doesnt become shoutting.

It's basically the magic E thing: Stope is pronounced differently to to stop ("the vowel says its name"), so stoping is pronounced differently to stopping. Like with magic E, this is only true with short vowels - shoute is pronounced the same as shout, so shoutting is pronounced the same as shouting. To put it another way, the consonant only needs to double to stop the vowel sound from changing.

Doubling is triggered under what I call "the hamburger rule". If you have a closed final syllable - or one-syllable word (consonant-vowel-consonant), then you have a hamburger, which is made up of bread-meat-bread.

Well, almost. A ball of meat becomes a hamburger patty when it is squashed under stress. So it's really only a hamburger when the syllable is stressed.

And if it's a hamburger, then it has to be a double cheeseburger (Big Mac). So you double the last consonant before adding -ing/-ed.